| 摘要 |
<p>PURPOSE:To avoid occurrence of the leak current for the nonselected memory to eliminate the possibility of breakdown, by turning off perfectly the nonselected memory FET via the resistance means between the common source of the memory MISFET and the earth potential terminal. CONSTITUTION:The control gates of the matrix-form memory MISFET-Q10-Q13 on the same line among the MISFET-Q10-Q17 are connected in common to the word line W1; while the control gates of Q14-Q17 are connected in common to the line Wm respectively. And the drains of Q10-Q14 in the same row are connected to bit line B1; and the drains of Q11-Q15 plus Q13-Q17 are connected to the corresponding bit lines B2-Bn each. When the line W1 is selected in the writing mode, the W1 increases up to the voltage VPP via the high resistance means Q18. And the writing current flows to the resistance means Q30 from the writing circuit 12 and via the selected Q10 to cause a reduction of voltage. As a result, a good OFF state can be held for the nonselected Q14 and the like even in case the potential of the floating gate may rise up.</p> |
